Panetta made the comments Monday during a foreign policy conference at the University of Oklahoma. Panetta says al-Qaida is an adaptive, resilient group of terrorists whose top goal is to attack the United States.

He says America's top priority is to strike back and ultimately defeat the terrorist organization.

Panneta says that in recent months counterterrorism activity has resulted in the deaths of half of al-Qaida's top 20 leaders. He says the CIA is effectively conducting operations that disrupt al-Qaida and that as a result, al-Qaida leaders are on the run.